1 files changed, 147 insertions, 0 deletions
diff --git a/debian/compute_pkgset.py b/debian/compute_pkgset.py
new file mode 100755
index 0000000..3404cb0
--- /dev/null
+++ b/debian/compute_pkgset.py
@@ -0,0 +1,147 @@
+#!/usr/bin/env python3
+
+import tempfile
+import pathlib
+import subprocess
+import debian.deb822
+from collections import defaultdict
+
+
+def main():
+    pkglist = defaultdict(lambda: defaultdict(set))
+    apttrusted = subprocess.check_output(
+        "eval $(apt-config shell v Dir::Etc::Trusted/f); printf $v", shell=True
+    ).decode()
+    apttrustedparts = subprocess.check_output(
+        "eval $(apt-config shell v Dir::Etc::TrustedParts/f); printf $v", shell=True
+    ).decode()
+    debci_arches = set(
+        ["amd64", "arm64", "armel", "armhf", "i386", "ppc64el", "riscv64", "s390x"]
+    )
+    # debci_arches = set(["amd64", "i386"])
+    for arch in list(debci_arches):
+        with tempfile.TemporaryDirectory() as tmpdir:
+            tmpdir = pathlib.Path(tmpdir)
+            (tmpdir / "etc" / "apt").mkdir(parents=True)
+            (tmpdir / "var" / "cache").mkdir(parents=True)
+            (tmpdir / "var" / "lib").mkdir(parents=True)
+            (tmpdir / "apt.conf").write_text(
+                f"""
+                Apt::Architecture "{arch}";
+                Apt::Architectures "{arch}";
+                Dir "{tmpdir}";
+                Dir::Etc::Trusted "{apttrusted}";
+                Dir::Etc::TrustedParts "{apttrustedparts}";
+            """
+            )
+            (tmpdir / "etc" / "apt" / "sources.list").write_text(
+                "deb http://deb.debian.org/debian/ unstable main"
+            )
+            subprocess.check_call(
+                ["apt-get", "update"], env={"APT_CONFIG": tmpdir / "apt.conf"}
+            )
+            indextargets = subprocess.check_output(
+                [
+                    "apt-get",
+                    "indextargets",
+                    "--format",
+                    "$(FILENAME)",
+                    "Created-By: Packages",
+                    f"Architecture: {arch}",
+                ],
+                env={"APT_CONFIG": tmpdir / "apt.conf"},
+            ).decode()
+            if not indextargets.strip():
+                print(f"skipping {arch}")
+                debci_arches.remove(arch)
+                continue
+            (tmpdir / "Packages").write_bytes(
+                subprocess.check_output(
+                    ["/usr/lib/apt/apt-helper", "cat-file", *indextargets.splitlines()]
+                )
+            )
+            pkgset = (
+                subprocess.check_output(
+                    [
+                        "grep-dctrl",
+                        "--no-field-names",
+                        "--show-field=Package",
+                        "--exact-match",
+                        "(",
+                        "--field=Essential",
+                        "yes",
+                        "--or",
+                        "--field=Priority",
+                        "required",
+                        "--or",
+                        "--field=Priority",
+                        "important",
+                        "--or",
+                        "--field=Priority",
+                        "standard",
+                        ")",
+                        (tmpdir / "Packages"),
+                    ]
+                )
+                .decode()
+                .splitlines()
+            )
+            pkgset.extend(
+                [
+                    "build-essential",
+                    "busybox",
+                    "gpg",
+                    "eatmydata",
+                    "usr-is-merged",
+                    "usrmerge",
+                ]
+            )
+            ceve = subprocess.check_output(
+                [
+                    "dose-ceve",
+                    f"--deb-native-arch={arch}",
+                    "-c",
+                    ",".join(pkgset),
+                    "-t",
+                    "deb",
+                    "-G",
+                    "pkg",
+                    "-T",
+                    "deb",
+                    (tmpdir / "Packages"),
+                ]
+            )
+        for pkg in debian.deb822.Packages.iter_paragraphs(ceve):
+            src = pkg.get("Source")
+            if src is None:
+                src = pkg["Package"]
+            elif " " in src:
+                src = src.split()[0]
+            pkglist[src][pkg["Package"]].add(arch)
+    result = []
+    for src in pkglist:
+        srcarches = set()
+        for pkg in pkglist[src]:
+            srcarches |= pkglist[src][pkg]
+        representers = [pkg for pkg in pkglist[src] if pkglist[src][pkg] == srcarches]
+        if not representers:
+            print(f"nothing represents {src}:", pkglist[src])
+            continue
+        pkg = sorted(representers)[0]
+        if pkglist[src][pkg] == debci_arches:
+            result.append(pkg)
+        else:
+            result.append(f"{pkg} [{' '.join(sorted(pkglist[src][pkg]))}]")
+    line = "Depends: "
+    for dep in sorted(result):
+        newline = line + f"{dep}, "
+        if len(newline) > 79:
+            print(line.removesuffix(" "))
+            line = f" {dep}, "
+        else:
+            line = newline
+    print(line.removesuffix(", "))
+
+
+if __name__ == "__main__":
+    main()